mirror of https://github.com/Kozea/pygal.git
Python to generate nice looking SVG graph
http://pygal.org/
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
319 lines
10 KiB
319 lines
10 KiB
#!/usr/bin/env python |
|
from itertools import izip, count, chain |
|
from lxml import etree |
|
|
|
from svg.charts.graph import Graph |
|
|
|
from util import float_range |
|
|
|
def get_pairs(i): |
|
i = iter(i) |
|
while True: yield i.next(), i.next() |
|
|
|
class Plot(Graph): |
|
"""=== For creating SVG plots of scalar data |
|
|
|
= Synopsis |
|
|
|
require 'SVG/Graph/Plot' |
|
|
|
# Data sets are x,y pairs |
|
# Note that multiple data sets can differ in length, and that the |
|
# data in the datasets needn't be in order; they will be ordered |
|
# by the plot along the X-axis. |
|
projection = [ |
|
6, 11, 0, 5, 18, 7, 1, 11, 13, 9, 1, 2, 19, 0, 3, 13, |
|
7, 9 |
|
] |
|
actual = [ |
|
0, 18, 8, 15, 9, 4, 18, 14, 10, 2, 11, 6, 14, 12, |
|
15, 6, 4, 17, 2, 12 |
|
] |
|
|
|
graph = SVG::Graph::Plot.new({ |
|
:height => 500, |
|
:width => 300, |
|
:key => true, |
|
:scale_x_integers => true, |
|
:scale_y_integerrs => true, |
|
}) |
|
|
|
graph.add_data({ |
|
:data => projection |
|
:title => 'Projected', |
|
}) |
|
|
|
graph.add_data({ |
|
:data => actual, |
|
:title => 'Actual', |
|
}) |
|
|
|
print graph.burn() |
|
|
|
= Description |
|
|
|
Produces a graph of scalar data. |
|
|
|
This object aims to allow you to easily create high quality |
|
SVG[http://www.w3c.org/tr/svg] scalar plots. You can either use the |
|
default style sheet or supply your own. Either way there are many options |
|
which can be configured to give you control over how the graph is |
|
generated - with or without a key, data elements at each point, title, |
|
subtitle etc. |
|
|
|
= Examples |
|
|
|
http://www.germane-software/repositories/public/SVG/test/plot.rb |
|
|
|
= Notes |
|
|
|
The default stylesheet handles upto 10 data sets, if you |
|
use more you must create your own stylesheet and add the |
|
additional settings for the extra data sets. You will know |
|
if you go over 10 data sets as they will have no style and |
|
be in black. |
|
|
|
Unlike the other types of charts, data sets must contain x,y pairs: |
|
|
|
[1, 2] # A data set with 1 point: (1,2) |
|
[1,2, 5,6] # A data set with 2 points: (1,2) and (5,6) |
|
|
|
= See also |
|
|
|
* SVG::Graph::Graph |
|
* SVG::Graph::BarHorizontal |
|
* SVG::Graph::Bar |
|
* SVG::Graph::Line |
|
* SVG::Graph::Pie |
|
* SVG::Graph::TimeSeries |
|
|
|
== Author |
|
|
|
Sean E. Russell <serATgermaneHYPHENsoftwareDOTcom> |
|
|
|
Copyright 2004 Sean E. Russell |
|
This software is available under the Ruby license[LICENSE.txt]""" |
|
|
|
top_align = right_align = top_font = right_font = 1 |
|
|
|
|
|
"""Determines the scaling for the Y axis divisions. |
|
|
|
graph.scale_y_divisions = 0.5 |
|
|
|
would cause the graph to attempt to generate labels stepped by 0.5; EG: |
|
0, 0.5, 1, 1.5, 2, ...""" |
|
scale_y_divisions = None |
|
"Make the X axis labels integers" |
|
scale_x_integers = False |
|
"Make the Y axis labels integers" |
|
scale_y_integers = False |
|
"Fill the area under the line" |
|
area_fill = False |
|
"""Show a small circle on the graph where the line |
|
goes from one point to the next.""" |
|
show_data_points = True |
|
"Indicate whether the lines should be drawn between points" |
|
draw_lines_between_points = True |
|
"Set the minimum value of the X axis" |
|
min_x_value = None |
|
"Set the minimum value of the Y axis" |
|
min_y_value = None |
|
"Set the maximum value of the X axis" |
|
max_x_value = None |
|
"Set the maximum value of the Y axis" |
|
max_y_value = None |
|
|
|
stacked = False |
|
|
|
@apply |
|
def scale_x_divisions(): |
|
doc = """Determines the scaling for the X axis divisions. |
|
|
|
graph.scale_x_divisions = 2 |
|
|
|
would cause the graph to attempt to generate labels stepped by 2; EG: |
|
0,2,4,6,8...""" |
|
def fget(self): |
|
return getattr(self, '_scale_x_divisions', None) |
|
def fset(self, val): |
|
self._scale_x_divisions = val |
|
return property(**locals()) |
|
|
|
def validate_data(self, data): |
|
if len(data['data']) % 2 != 0: |
|
raise ValueError("Expecting x,y pairs for data points for %s." % self.__class__.__name__) |
|
|
|
def process_data(self, data): |
|
pairs = list(get_pairs(data['data'])) |
|
pairs.sort() |
|
data['data'] = zip(*pairs) |
|
|
|
def calculate_left_margin(self): |
|
super(Plot, self).calculate_left_margin() |
|
label_left = len(str(self.get_x_labels()[0])) / 2 * self.font_size * 0.6 |
|
self.border_left = max(label_left, self.border_left) |
|
|
|
def calculate_right_margin(self): |
|
super(Plot, self).calculate_right_margin() |
|
label_right = len(str(self.get_x_labels()[-1])) / 2 * self.font_size * 0.6 |
|
self.border_right = max(label_right, self.border_right) |
|
|
|
def data_max(self, axis): |
|
data_index = getattr(self, '%s_data_index' % axis) |
|
max_value = max(chain(*map(lambda set: set['data'][data_index], self.data))) |
|
# above is same as |
|
#max_value = max(map(lambda set: max(set['data'][data_index]), self.data)) |
|
spec_max = getattr(self, 'max_%s_value' % axis) |
|
max_value = max(max_value, spec_max) |
|
return max_value |
|
|
|
def data_min(self, axis): |
|
data_index = getattr(self, '%s_data_index' % axis) |
|
min_value = min(chain(*map(lambda set: set['data'][data_index], self.data))) |
|
spec_min = getattr(self, 'min_%s_value' % axis) |
|
if spec_min is not None: |
|
min_value = min(min_value, spec_min) |
|
return min_value |
|
|
|
x_data_index = 0 |
|
y_data_index = 1 |
|
def data_range(self, axis): |
|
side = {'x': 'right', 'y': 'top'}[axis] |
|
|
|
min_value = self.data_min(axis) |
|
max_value = self.data_max(axis) |
|
range = max_value - min_value |
|
|
|
side_pad = range / 20.0 or 10 |
|
scale_range = (max_value + side_pad) - min_value |
|
|
|
scale_division = getattr(self, 'scale_%s_divisions' % axis) or (scale_range / 10.0) |
|
|
|
if getattr(self, 'scale_%s_integers' % axis): |
|
scale_division = round(scale_division) or 1 |
|
|
|
return min_value, max_value, scale_division |
|
|
|
def x_range(self): return self.data_range('x') |
|
def y_range(self): return self.data_range('y') |
|
|
|
def get_data_values(self, axis): |
|
min_value, max_value, scale_division = self.data_range(axis) |
|
return tuple(float_range(*self.data_range(axis))) |
|
|
|
def get_x_values(self): return self.get_data_values('x') |
|
def get_y_values(self): return self.get_data_values('y') |
|
|
|
def get_x_labels(self): |
|
return map(str, self.get_x_values()) |
|
def get_y_labels(self): |
|
return map(str, self.get_y_values()) |
|
|
|
def field_size(self, axis): |
|
size = {'x': 'width', 'y': 'height'}[axis] |
|
side = {'x': 'right', 'y': 'top'}[axis] |
|
values = getattr(self, 'get_%s_values' % axis)() |
|
max_d = self.data_max(axis) |
|
dx = float(max_d - values[-1]) / (values[-1] - values[-2]) |
|
graph_size = getattr(self, 'graph_%s' % size) |
|
side_font = getattr(self, '%s_font' % side) |
|
side_align = getattr(self, '%s_align' % side) |
|
result = (float(graph_size) - self.font_size*2*side_font) / \ |
|
(len(values) + dx - side_align) |
|
return result |
|
|
|
def field_width(self): return self.field_size('x') |
|
def field_height(self): return self.field_size('y') |
|
|
|
def draw_data(self): |
|
self.load_transform_parameters() |
|
for line, data in izip(count(1), self.data): |
|
x_start, y_start = self.transform_output_coordinates( |
|
(data['data'][self.x_data_index][0], |
|
data['data'][self.y_data_index][0]) |
|
) |
|
data_points = zip(*data['data']) |
|
graph_points = self.get_graph_points(data_points) |
|
lpath = self.get_lpath(graph_points) |
|
if self.area_fill: |
|
graph_height = self.graph_height |
|
path = etree.SubElement(self.graph, 'path', { |
|
'd': 'M%(x_start)f %(graph_height)f %(lpath)s V%(graph_height)f Z' % vars(), |
|
'class': 'fill%(line)d' % vars()}) |
|
if self.draw_lines_between_points: |
|
path = etree.SubElement(self.graph, 'path', { |
|
'd': 'M%(x_start)f %(y_start)f %(lpath)s' % vars(), |
|
'class': 'line%(line)d' % vars()}) |
|
self.draw_data_points(line, data_points, graph_points) |
|
self._draw_constant_lines() |
|
del self.__transform_parameters |
|
|
|
def add_constant_line(self, value, label = None, style = None): |
|
self.constant_lines = getattr(self, 'constant_lines', []) |
|
self.constant_lines.append((value, label, style)) |
|
|
|
def _draw_constant_lines(self): |
|
if hasattr(self, 'constant_lines'): |
|
map(self.__draw_constant_line, self.constant_lines) |
|
|
|
def __draw_constant_line(self, (value, label, style)): |
|
"Draw a constant line on the y-axis with the label" |
|
start = self.transform_output_coordinates((0, value))[1] |
|
stop = self.graph_width |
|
path = etree.SubElement(self.graph, 'path', { |
|
'd': 'M 0 %(start)s h%(stop)s' % vars(), |
|
'class': 'constantLine'}) |
|
if style: |
|
path.set('style', style) |
|
text = etree.SubElement(self.graph, 'text', { |
|
'x': str(2), |
|
'y': str(start - 2), |
|
'class': 'constantLine'}) |
|
text.text = label |
|
|
|
def load_transform_parameters(self): |
|
"Cache the parameters necessary to transform x & y coordinates" |
|
x_min, x_max, x_div = self.x_range() |
|
y_min, y_max, y_div = self.y_range() |
|
x_step = (float(self.graph_width) - self.font_size*2) / \ |
|
(x_max - x_min) |
|
y_step = (float(self.graph_height) - self.font_size*2) / \ |
|
(y_max - y_min) |
|
self.__transform_parameters = dict(vars()) |
|
del self.__transform_parameters['self'] |
|
|
|
def get_graph_points(self, data_points): |
|
return map(self.transform_output_coordinates, data_points) |
|
|
|
def get_lpath(self, points): |
|
points = map(lambda p: "%f %f" % p, points) |
|
return 'L' + ' '.join(points) |
|
|
|
def transform_output_coordinates(self, (x,y)): |
|
x_min = self.__transform_parameters['x_min'] |
|
x_step = self.__transform_parameters['x_step'] |
|
y_min = self.__transform_parameters['y_min'] |
|
y_step = self.__transform_parameters['y_step'] |
|
#locals().update(self.__transform_parameters) |
|
#vars().update(self.__transform_parameters) |
|
x = (x - x_min) * x_step |
|
y = self.graph_height - (y - y_min) * y_step |
|
return x,y |
|
|
|
def draw_data_points(self, line, data_points, graph_points): |
|
if not self.show_data_points \ |
|
and not self.show_data_values: return |
|
for ((dx,dy),(gx,gy)) in izip(data_points, graph_points): |
|
if self.show_data_points: |
|
etree.SubElement(self.graph, 'circle', { |
|
'cx': str(gx), |
|
'cy': str(gy), |
|
'r': '2.5', |
|
'class': 'dataPoint%(line)s' % vars()}) |
|
if self.show_data_values: |
|
self.add_popup(gx, gy, self.format(dx, dy)) |
|
self.make_datapoint_text(gx, gy-6, dy) |
|
|
|
def format(self, x, y): |
|
return '(%0.2f, %0.2f)' % (x,y)
|
|
|